Techno-economic feasibility and comparison of coal water slurry concentration on a coal to methanol plant with consideration of carbon capture and storage

In this study, the effect of slurry concentration and carbon dioxide capture and storage (CCS) equipment on the techno-economic feasibility of a coal-to-methanol (CTM) process with coal water slurry (CWS) gasification are investigated, while the effective means to improve the economic benefit of methanol factory are proposed. The sensitive factors including production scale, coal price, and carbon tax are investigated, especially the CWS concentration is compared at 63% and 68% scenarios. A CTM plant with 180 x 104 t/a production scale shows that the saving cost could reach 29.20 x 106 US$ and the CO2 emission could be reduced by 0.65 x 106 t/a every year as the CWS concentration increases. The investment in CCS equipment would increase the production cost (PC) per methanol raising by 7-8%, while the CCS introduction would effectively alleviate the PC increment caused by the carbon tax. Note that as the carbon tax exceeded 9.42 US$/t, the benefit for CCS on the reduction of PC would be more significant. The outcomes of this study have suggested that increasing the CWS concentration is an effective method to reduce the PC and improve the economic benefit. The CCS technology could effectively reduce CO2 emissions and mitigate the raising of PC caused by carbon tax. The findings have manifested a well feasibility for environment benefit improvement by solid content increasing and CCS introduction in response to energy and environmental challenges for the cleaner production and sustainable development.